Dairy Beef Research Articles

Dose Effect of Drinking Water Nitrate on Health, Feed Intake, Rumen Fermentation and Microbiota, and Nitrogen Excretion in Holstein Heifers for a Sustainable Water Use

The present study aimed to evaluate the potential hazardous effects of NO3− concentration in drinking water on health, feed intake, rumen fermentation and microbiota, and nitrogen excretion of Holstein heifers fed a high-concentrate diet for a sustainable water use. Twenty-four Holstein heifers were individually allocated and assigned to one of four treatments with increasing drinking water NO3− concentration: CTR, without NO3−; LOW, with 44 mg NO3−/L; MOD, with 110 mg NO3−/L; and HIGH, with 220 mg NO3−/L. The entire study lasted 168 days. Fortnightly water NO3− concentration and daily feed and water intake were recorded. Blood parameters, rumen pH, volatile fatty acids, NO3− and NO2− concentration, microbiota, and apparent total tract digestibility were determined at the beginning and at the end of the study. Most of the analyzed parameters were similar among treatments. Denitrifying bacteria population, estimated as nosZ gene copies, were greater in HIGH animals than in CTR animals at the end of the study. In conclusion, drinking water NO3− concentration up to 220 mg/L has no detrimental effect on health, feed intake, rumen fermentation, nor N excretion in dairy beef cattle for periods up to 168 days; moreover, denitrifying bacteria population increased, which are related with the neutralization of the greenhouse gas N2O.

Bovine Respiratory Disease (BRD) in Post-Weaning Calves with Different Prevention Strategies and the Impact on Performance and Health Status

Our study aimed to compare Bovine Respiratory Disease (BRD) morbidity, mortality, and growth in dairy and dairy beef cross-bred calves during the commingle period, 81–120 days of age, using two different BRD prevention strategies. The calves (n = 1799) were randomly assigned into groups: (1) Control (CON; received no vaccine or metaphylaxis); (2) Tulathromycin metaphylaxis (TUL; IncrexxaTM, Elanco Animal Health Inc., Greenfield, IN, USA); and (3) Mannheimia haemolytica vaccine (VACC; Nuplura® PH, Elanco Animal Health Inc., Greenfield, IN, USA). Calves were individually weighed three times during the study to estimate average daily gain (ADG). Deep nasopharyngeal swabs, thoracic ultrasonography, health scores, and treatment records were collected during the study. Ultrasound and health score results were not different across treatments. In this study, the TUL group had a lower cumulative BRD incidence than CON. The cumulative incidence and 95% CI of BRD during the commingle period, 81–120 days of age for CON, TUL, and VACC were 0.43 (0.38 to 0.47), 0.36 (0.38 to 0.40), and 0.39 (0.35 to 0.43), respectively. The ADG for CON, TUL, and VACC were 0.25 ± 0.15, 0.32 ± 0.15, and 0.17 ± 0.15 kg, respectively. There was no difference among the treatment groups for ADG. Management and environmental conditions were variable at this operation throughout the study period and likely impacted the calves. Earlier interventions may be needed when the BRD incidence is elevated in high-risk calves.

PSIX-21 Can seeds rich in polyunsaturated fatty acids reduce methane emissions when substituting palm oil on dairy beef calves fed high-concentrate diets? In vitro screening

Abstract The aim of this study was to evaluate the rumen in vitro methane (CH4) production of concentrates feed with a different protein source (PS) replacing partially palm oil by different seeds (SE) rich in polyunsaturated fatty acids (PUFA). Concentrate PS were: T1 = 8% soybean meal; and T2 = 15% dried distillers grain. Palm oil (CTR; 4% and 3.5% for T1 and T2, respectively) was partially substituted (1%) by flax seed (FL; 2.7%), canola seed (CO; 3%) or sunflower seed (SU; 2.3%), thus 8 concentrates were tested. Samples were ground at 1-mm and used in an in vitro digestibility assay. The rumen liquid was obtained at the slaughterhouse. Two incubation sets were done; two sampling points lasted 24 and 48 h to calculate the dry matter (DM) digestibility; a third sampling point lasted 12 d to monitor the CH4 production. Data were analyzed using a mixed effects model. Net volume of CH4 per degraded DM presented a PS effect (P < 0.01); T1 produced greater net volume of CH4 per degraded DM than T2 (8.12 vs. 6.91 ± 0.330 ml/mg, respectively). Furthermore, net volume of CH4 per degraded DM presented a SE effect (P < 0.01); all concentrates with seeds tested reduced the net volume of CH4 per degraded DM compared with CTR, and specifically CO produced lower net volume of CH4 per degraded DM than FL and SU (8.91, 7.47, 6.28, 7.39 ± 0.467 ml/mg; CTR, FL, CO, SU, respectively). In conclusion, the use of flax, canola, or sunflower seeds to partially substitute palm oil in concentrate feed, regardless of its PS, can be potential strategies to reduce rumen CH4 emissions, and seems that canola seed may be the most effective one.

PSXI-22 Effects of a palatability enhancer and olive bioactives on performance and physiological status of veal calves after farm reception

Abstract Veal calves have to deal with several stressors early in life, such as transport and commingling with animals of unknown health histories from multiple different origins; making the reception a possible critical period where animals should adapt to all these challenges. Previous studies in unweaned rosée calves have shown that the use of feed additives (FA) to enhance intake and immunity at farm arrival could be a strategy to minimize the negative effects of stress and feed restriction during transportation. The aim of this study was to evaluate the effects of a palatability enhancer (PE) and olive bioactives (OB) on performance and serum biomarkers in veal calves. Dairy beef calves [n = 252; BVD-free; body weight (BW) = 44.6 ± 3.63 kg] coming from auction market were distributed in 3 treatments (84 animals/tr) during 8 wk: i) calves fed concentrate and MR without FA (negative control, NC); ii) calves fed concentrate and MR with a PE based on sweeteners (PE); and iii) calves fed concentrate with PE and MR with PE and OB (PEOB). On farm arrival animals were housed individually until 5 wk of age, when animals were grouped in pens of 4 calves. Performance was monitored during the trial and serum samples were collected 48 h after the mixing (25 animals/tr) to analyze several biomarkers related to immune system (MILLIPLEX MAP Kit) and energy status (BHBA). Performance data were analyzed with a mixed-effects model and serum biomarkers by One-Way Anova with Fisher’s LSD correction for multiple comparisons (normally distributed data) or by non-parametric Kruskal-Wallis test with Dunn’s correction (data not normally distributed). Final BW was greater (P = 0.01) in PE and PEOB groups compared with NC (+2.2 kg and +2.6 kg, respectively). Concentrate feed intake (FI) during first 4 wk tended (P = 0.06) to be greater in PEOB compared with NC (+15%); however, after grouping (wk 5 to wk 8), PE showed a ldecreased FI compared with NC (-9.5%, P = 0.01). Forty-eight hours after animal grouping, PEOB showed reduced concentration of tumor necrosis factor (TNF) α than NC and PE (P = 0.03). Moreover, PEOB and PE had a greater concentration of interleukin (IL) 36Rα (P < 0.05) and IP10 (P < 0.01) compared with NC. Besides PEOB tended (P < 0.15) to have decreased concentrations of MIP1α, IL1α, and BHBA compared with PE. In conclusion, the addition of a PE and OB improved the adaptation of veal calves after reception, resulting in greater final BW. The improvement in early FI and the immunomodulatory effect in challenging situations displayed by the treatments may partially explain the observed benefits.

PSXII-23 Effect of dietary straw withdrawal in high-concentrate diets on animal behavior in dairy beef crossbred bulls housed with straw bedding

Abstract The aim of this study was to evaluate the effect of dietary straw withdrawal in high-concentrate diets on animal behavior in dairy beef crossbred bulls housed with straw bedding. Bulls [n = 93; body weight (BW) = 335 ± 9.0 kg, and 218 ± 4.0 d of age) were group-housed in a partially opened barn with 6 pens straw-bedded cleaned every 2 wk. Animals were assigned to one of 3 different feed programs: 1) CTR (n = 32), concentrate (13.1% crude protein (CP), 5.9% fat content, 16.1% neutral detergent fiber (NDF), 40.8% starch content) and straw ad libitum fed in two separate feeders; 2) TSW (n = 32), like CTR; however, dietary straw withdrawal took place the first 84 study days; and 3) NSS (n = 29), concentrate with a lower starch content (12.2% CP, 4.6% fat content, 22.0% NDF, 39.6% starch content) without a dietary straw for the whole study. The study lasted 155 d divided into eleven 14-d periods. General activities and postures were recorded through scan sampling every 5 min, and social behavior was recorded during 5 min of continuous sampling in two rounds of 15 min. Social behaviors were transformed to a log scale to achieve a normal distribution. Data were analyzed with a mixed-effects model. The first period was an adaptation where a dietary straw bale per pen was offered in all treatments; thereafter, only in CTR, and in TSW after period 6. Percentage of bulls eating at the concentrate feeder was greater (P = 0.05) in NSS than in CTR and TRW (5.87 vs. 4.64 and 4.82 ± 0.038 %, respectively). The percentages of bulls ruminating at the beginning of the study were greater (P < 0.01) in CTR compared with TSW and NSS, but after dietary straw was offered in TSW, the percentages of bulls ruminating increased in TSW and were greater in CTR and TSW than in NSS. At the beginning of the study, during the dietary straw withdrawal in TSW bulls, the number of oral behaviors and stereotypies were greater (P < 0.01) in TSW than in CTR, but after straw offer in TSW oral behaviors and stereotypies were only greater in NSS than in CTR and TSW. In conclusion, short- and long-term dietary straw withdrawal increased behaviors indicative of poor animal welfare regardless of the starch content in the concentrate in dairy beef crossbred bulls fed high-concentrate diet housed with straw bedding.

PSXIII-1 Sensory additives improved the recovery of commercially marketed and transported unweaned dairy beef calves at rearing farm arrival

Abstract Calf recovery after arrival at the rearing farm in unweaned calves is impaired by periods of stress, feed restriction and fasting during marketing and transportation. The use of feed additives to enhance intake at arrival could be a strategy to minimize those negative effects. A total of 72 calves (71.4 ± 1.72 kg) gathered in a commercial assembly center and transported 9 h to a rearing farm were used to evaluate the effect of a sensory additive (SA) on performance in calves fed 2 L of milk replacer twice daily at 12.5% and ad libitum concentrate feed. Calves were allocated in 8 pens and distributed in 2 treatments (4 pens/treatment): calves fed a concentrate without SA since the beginning of the study (arrival to the rearing farm after transport) until weaning (CON; n = 36); calves fed a concentrate containing SA (SEN; n = 36) from arrival until weaning. Calf body weight (BW) and pen intake were recorded weekly. On d 21 of the study, calves were partially weaned and only milk replacer was offered in the morning, and on d 28 all calves were completely weaned. The study lasted 35 d. Data were analyzed with a mixed-effects model. Average daily gain was greater (P = 0.04) for SEN calves compared with CON calves (0.68 ± 0.019 kg/d and 0.61 ± 0.019 kg/d, respectively). Final BW of SEN calves (95.5 ± 0.89 kg) tended (P = 0.06) to be greater compared with BW of CON calves (93.1 ± 0.89 kg). Finally, average concentrate intake was greater for SEN calves (0.89 ± 0.023 kg/d) compared with CON calves (0.79 ± 0.023 kg/d). Unweaned dairy beef calves receiving sensory additive improved concentrate intake and growth at farm arrival improving their recovery.

407 Transition from the ranch to the feedyard: Challenges and management strategies to improve calf health welfare and performance

Abstract The health, welfare and performance of newly received feedlot calves is intricately connected to their pre- and post-weaning management as well as how they are transitioned from the ranch to the feedyard. Industry data suggest that despite prophylactic antimicrobial use in receiving calves the incidence of respiratory related morbidity and mortality has remained unchanged in Canadian feedyards for the past 4 decades. It is well established that any management practice causing stress or pain has an immunosuppressive effect thereby increasing the risk of calf morbidity and mortality and reducing performance efficiency. There are several factors that could contribute to this including, if and or how preconditioning is conducted, comingling at assembly yards or auctions and number of calf sources, and the distance calves are transported and the effects of rest. The impacts of other timely and relevant factors such as environmental conditions (rapid and extreme weather/temperature changes) and cattle type (dairy beef or dairy beef cross) will also be covered. Studies assessing these impacts on receiving calf health, welfare and performance as well as potential strategies for mitigating negative effects will be discussed.

253 Effect of dietary straw withdrawal in high-concentrate diets on efficiency, carcass performance, rumen characteristics and seized livers in dairy beef crossbred bulls housed with straw bedding

Abstract The aim of this study was to evaluate the effect of dietary straw withdrawal in high-concentrate diets on efficiency, carcass performance, rumen characteristics and seized livers in dairy beef crossbred bulls housed with straw bedding. Bulls [n = 93; 335 ± 9.0 kg body weight (BW); 218 ± 4.0 d age] were group-housed in 6 straw-bedded pens according to 3 different feeding programs (2 pens/treatment): 1) CTR (n = 32), concentrate (13.1% CP, 5.9% fat content, 16.1% NDF, 40.8% starch content) and straw ad libitum fed in two separate feeders; 2) TSW (n = 32), like CTR, however, dietary straw withdrawal took place the first 84 study days; and 3) NSS (n = 29), concentrate with a reduced starch content (12.2% CP, 4.6% fat content, 22.0% NDF, 39.6% starch content) without dietary straw for the whole study. The study lasted 155 d divided into eleven 14-d periods. Individual concentrate intake was recorded daily, and dietary straw consumption was recorded per pen biweekly, as was individual BW. Carcass performance, rumen characteristics and seized organs were recorded at the slaughterhouse. Data were analyzed with a mixed-effects model. The first period was an adaptation where a dietary straw bale per pen was offered in all treatments; thereafter, only in CTR, and in TSW, after period 6. Treatment by period interactions (P < 0.01) in efficiency parameters were observed. Specifically, BW was greater in CTR than in TSW and NSS bulls while straw withdrawal periods; however, TSW bulls increased BW compared with NSS bulls when dietary straw was reintroduced, with final BW greater in CTR and TSW than in NSS bulls (569, 557 and 536 ± 8.0 kg, respectively). Regarding feed consumption, while dietary straw withdrawal for the first 6 periods, concentrate and straw intake were less in TSW and NSS than in CTR bulls, regardless the type of concentrate; after period 7, concentrate intake did not differ among treatments, and straw intake was greater in CTR and TSW than in NSS bulls, except in period 7, just after dietary straw reintroduction, that was greater in TSW than in CTR bulls. Hot carcass weight was greater (P < 0.01) in CTR than in TSW and NSS bulls (314, 296 and 299 ± 6.0 kg, respectively); dressing percentage was greater (P < 0.01) in CTR and NSS than in TSW bulls (55.1, 55.9 and 53.2 ± 0.65%, respectively); and carcass conformation tended (P = 0.06) to have greater classification in CTR bulls, and reduced classification in TSW bulls. Number of sized livers tended (P = 0.07) to be greater in NSS than in CTR and TSW bulls (22, 3 and 9%, respectively). In conclusion, short and long-term dietary straw withdrawal decreased animal and carcass performance regardless concentrate’s starch content in dairy beef crossbred bulls fed high-concentrate diets housed with straw bedding.

PSIV-22 Use of a mixture of olive pomace extract, a palatability enhancer and tributyrin as feed additive on the recovery of unweaned dairy beef calves with pneumonia at farm arrival

PSIV-22 Use of a mixture of olive pomace extract, a palatability enhancer and tributyrin as feed additive on the recovery of unweaned dairy beef calves with pneumonia at farm arrival

Prospective life cycle assessment of an integrated biorefinery for production of lactic acid from dairy side streams

In Ireland, the world's first-of-a-kind integrated dairy biorefinery has been developed to address waste disposal challenges in the dairy industry by converting dairy side streams into high-value biochemicals, specifically lactic acid (LA). This study aims to assess the environmental impacts of this innovative technology at a commercial scale through a comprehensive life cycle assessment (LCA) study. Experimental data from a pilot-plant facility was scaled up to a production capacity of 20,000 tons of LA per year using SuperPro Designer®. This data was combined with information from upstream processes such as milk production, cheese production, and transport, using OpenLCA. The cradle-to-gate LCA revealed that milk production had the greatest overall impact across all categories. Enteric fermentation has the most significant impact on climate change, while fertilizer and concentrate feed production primarily contributed to non-renewable energy demand, ozone formation, human toxicity, water consumption and fossil depletion. Fertilizer application substantially influenced eutrophication, acidification and ecotoxicity indicators. However, scenario analysis showed that implementing strategies like substituting biorefinery byproducts with fossil-based products, increasing renewable energy penetration, and integrating dairy beef production could result in significant environmental savings across all impact categories. Moreover, the findings highlighted that the handling of co-products would determine the magnitude of the system's impact. This study concludes that combining process design analysis with accessible data at a higher Technology readiness level (TRL) 7 offers an opportunity to identify hotspots and recommend alternative strategies to improve the environmental sustainability of the whole system at the design stage. Additionally, this study provides valuable guidance for minimizing environmental impacts during the design phase, enabling informed investment decisions before construction. Ultimately, it plays a crucial role in establishing a circular bioeconomy within the dairy industry by effectively utilizing the side streams to produce sustainable biobased chemicals, specifically LA.

Chlorine dioxide may be an alternative to acidification and chlorination for drinking water chemical disinfection in dairy beef bulls

Alternative water disinfectants to chlorination need to be identified because its effectiveness is limited by water pH and potentially carcinogen by−products resulted from chlorination and organic compound reaction. The first study aimed to evaluate the effect of different drinking water chemical disinfection treatments on water quality, its potential hazard effects on animal health, water and feed consumption, and apparent total tract digestibility in dairy beef bulls fed high-concentrate diets. For 224 days, 24 Holstein bulls (176 ± 16.3 kg BW, and 149 ± 5.8 days of age) were individually assigned to one of four treatments with different drinking water chemical disinfectants: without disinfection (CTR); acidification and chlorination (ACCHL; 0.65 mL/L H3PO4 and 0.14 mL/L NaClO 15%); hydrogen peroxide (PER; 0.15 mL/L); and chlorine dioxide (DIO; 2.50 mL/L). Data were analysed with a mixed-effects model. Treatments affected the chemical characteristics of the water: in ACCHL, pH was 6.60 and free residual chlorine was 0.75 mg/L; in PER, H2O2 was 10.6 mg/L; and in DIO, ClO2 was 0.52 mg/L. Water physicochemical quality parameters in all treatments were below maximal thresholds established for safe water consumption by the Water Safety Royal Decree (RD 140/2003). In addition, the total coliform count of treated waters was reduced (P = 0.01) compared with CTR; moreover, ACCHL and DIO treatments were more effective in reducing total coliform count than PER. Dry matter intake tended (P = 0.07) to increase in DIO compared with CTR. Treatments did not affect blood parameters nor apparent total tract digestibility. The second study aimed to evaluate the potential benefit on animal performance of two drinking water disinfectants under commercial conditions in dairy beef crossbred Holstein bulls fed high-concentrate diets. Ninety-six animals (307 ± 4.4 kg BW, and 224 ± 1.8 days of age) were allocated to six pens for 140 days and assigned to one of two treatments: ACCHL, most common water disinfectant, and DIO. Data were analysed with a mixed-effects model. Water total coliform count and water consumption were similar between treatments. Concentrate intake was greater (P = 0.02) in ACCHL for the last 14 study days. Growth performance and carcass quality were similar between treatments. In summary, acidification and chlorination, H2O2, and ClO2 as drinking water disinfectants in dairy beef bulls had good disinfecting activity without detrimental effects on health and nutrient digestibility, and performance.

Bovine respiratory disease (BRD) in postweaning calves with different prevention strategies and the impact on performance and health status

Bovine respiratory disease (BRD) is one of the most common causes of morbidity and mortality in bovine calves, especially around the weaning period, when the calves are usually moved from individual to group housing. BRD has negative perfor­mance and economic consequences that extend well beyond the actual event. Therefore, we aimed to compare BRD morbid­ity, mortality and growth in dairy and dairy beef cross-bred calves during the first commingle groups using 2 different BRD prevention strategies. We hypothesized that one or both pre­vention strategies would reduce BRD morbidity and mortality, resulting in better health status and performance in calves.

147 Effects of grazing dairy-beef and native beef crossbred steers on native range with supplementation on growth

Abstract Our objective was to evaluate the effects of grazing dairy-beef crossbred and native beef crossbred steers on native range with supplementation on growth. Dairy-beef (DB) steers (n = 75) were acquired and transported 214 km from Buffalo Feeders at Buffalo, OK. Native beef (NB) steers (n = 75) were acquired and transported 647 km from Capitol Land and Livestock at Schwertner, TX. All steers were transported to the Marvin Klemme Range Research Station in Bessie, OK. Steers were rested for 48 h and received ad libtum access to mixed grass hay and water. Steers were allocated by BW and randomly assigned to pasture based on a stocking rate of 2.43 ha/animal. Animals grazed 3 native pastures (pasture 1; n = 39, pasture 2; n = 52, pasture 3; n = 59), and pastures were balanced for breed type (pasture 1; DB = 21; NB = 18, pasture 2; BD = 26; NB = 26, pasture 3; DB = 28; NB = 31). Steers were supplemented with extruded 100% DDGS cubes (MasterHand Milling, Lexington, NE) at 0.45 kg per animal per day for the first 53 d. As forage maturity increased and 53-d body weights (BW) were taken, supplementation increased to 1.13 kg per animal per day. Initial BW was 8 ± 3 kg greater (P = 0.01) in DB steers than the NB steers. Native beef steers weighed 16 ± 4 kg heavier (P < 0.01) on d 60 and weighed 24 ± 5 kg heavier (P < 0.01) at final BW than the DB steers. Average daily gain for NB steers was greater (P < 0.01) by 0.46 ± 0.04 kg in the first 53 d and was greater (P = 0.01) by 0.11 ± 0.04 kg for d 53 to 145 than DB. Native beef steers also had a greater (P < 0.01) overall ADG by 0.22 ± 0.02 kg. There were no differences (P = 0.55) in breed for those treated and re-retreated for issues such as pinkeye, foot rot, and BRD. Based on these results, breed of cattle grazing native rangeland in Southwestern Oklahoma with supplementation had an impact on performance, but no impact on treatment of respiratory and non-respiratory issues.

335 Use of Feed Additives Added to the Milk Replacer and Concentrate Or Only to the Concentrate in Unweaned Dairy Beef Calves After Transportation and Its Effects on Performance

Abstract Previous studies have shown that the use of additives to enhance intake and immunity at farm arrival could be a strategy to minimize the negative effects of stress and feed restriction during transportation in unweaned calves. Unweaned dairy beef calves are fed low liquid feeding programs to avoid mechanical diarrheas and to enhance the consumption of solid feed to increase growth. A total of 78 dairy beef calves (57.8 ± 1.64 kg) coming from auction market were used to evaluate the effect of various feed additives [FA; comprising palatability enhancers (PE), standardized olive pomace extract (OE), and tributyrin (TB)] added to the milk replacer (MR) and concentrate or only to the concentrate on performance until 1 week after weaning. Calves were distributed in 6 treatments: calves fed MR and concentrate without FA (CTR-CTR; n = 13); calves fed MR without FA and concentrate with PE (CTR-PE; n = 13); calves fed MR without FA and concentrate with complete mixture OE + TB + PE (CTR-COM; n = 13); calves fed MR and concentrate with PE (PEPE; n = 13); calves fed MR with PE and concentrate with complete mixture OE + TB + PE (PE-COM; n = 13); calves were fed MR with complete mixture OE + TB + PE and concentrate with PE (COM-PE; n = 13). At arrival calves were only fed 2 L of MR twice daily at 12.5% and concentrate feed ad libitum. On day 35 of the study, animals were submitted to a social stress challenge, calves within one treatment were mixed for 24 h, and on day 36, calves returned to their home pens and the afternoon milk was removed. On day 42, all calves were weaned, and they were followed until day 49. Data were analyzed with a mixed-effects model. No differences were observed in concentrate intake the first week after transportation. However, an interaction between treatment and time (P < 0.01) was observed among treatments in concentrate intake from day 35 until day 49 when calves were already weaned. The PE-PE and PE-COM calves had a greater (P < 0.10) concentrate intake from day 28 to day 42 than CTR-CTR or CTR-PE calves, while from day 42 to day 49 the CTR-COM was the group of calves with the greatest concentrate intake. Although no differences were observed on final BW among treatments, the CTR-COM calves had numerically greater ADG than the rest of the treatments. In unweaned dairy beef calves with liquid feeding restriction, the mixture of palatability enhancers, standardized olive pomace extract, and tributyrin potentially increases concentrate intake and growth when added in the concentrate feed.

PSII-30 Effect of Dietary Alpha-Amylase Enzyme Supplementation on Growth Performance and Carcass Quality of Crossbred Dairy Beef Bulls Fed Pellet Or Mash High-Concentrate Diets

Abstract The aim of this study was to evaluate the effect of dietary alpha-amylase supplementation on growth performance and carcass quality in crossbred dairy beef bulls fed either pellet or mash high-concentrate diets. Two parallel studies were conducted in two barns. In the first barn, 138 bulls (170 ± 2.3 kg of BW, and 148 ± 0.7 days of age) were grouped in 8 pens of 16 to 19 animals/pen and fed pelleted concentrate (PELLET study); and in the second barn, 148 (180 ± 1.6 kg of BW, and 150 ± 0.7 days of age) were grouped in 8 pens of 17 to 19 animals/pen and fed mash concentrate (MASH study). All bulls were fed concentrate (Table 1), straw, and water ad libitum. In each study, pens were assigned to one of 2 treatments: 1) CTR, no amylase supplementation; 2) RUM, RumiStar600 CT concentrate inclusion [630 mg/kg DM, based on 600 kilo novo units (KNU) of alpha-amylase activity]. After 196 days, divided in seven 28-days periods, where daily concentrate intake per pen, and BW per animal every 28 days was recorded animals were transported to slaughterhouse at different days within a month. Also, on days 0, 42, 84 and 168 concentrate samples were collected for enzyme activity and nutrient content analyses. Carcass quality was recorded at the slaughterhouse, bulls of PELLET study were slaughtered on average at 236 days of study and bulls of MASH study were slaughtered on average at 226 days of study. Data of each study were analyzed using a mixed model. In PELLET study, growth performance and carcass quality were not affected by treatments; however, conformation grade (SEUROP) was improved (P = 0.03) in RUM bulls compared with CTR bulls (score R: 18 vs. 5 %; score O: 54 vs. 56 %; score P: 28 vs. 39 %; RUM vs. CTR, respectively). Moreover, feed conversion ratio (FCR) was numerically (P = 0.11) improved in RUM fed bulls compared with CTR fed bulls (4.65 vs. 4.99 kg DM/kg, RUM vs. CTR, respectively;). In the MASH study, only an interaction between treatment by time in BW (P = 0.04) was observed; RUM bulls tended to be heavier than CTR bulls in the period 7 (476 vs. 470 ± 3.2 kg, RUM vs. CTR, respectively; P = 0.10). In conclusion, in crossbred dairy beef bulls fed high-concentrate diets with alpha-amylase supplementation (600 KNU of alpha-amylase activity/kg DM of concentrate) for at least 196 days improved FCR and carcass conformation grade when concentrate presentation form was pellet.

PSXI-1 A Case Study of the Environmental Footprint of Dairy-Beef Production in Catalonia: a Tool to Improve Sustainability

Abstract This study aims to assess the environmental impact of the dairy beef meat value chain in Catalonia, north-eastern Spain, from cradle to distribution, using the methodology recommended by the European Commission’s in its Product Environmental Footprint (PEF; EC, 2021) initiative. Case studies and the construction of regionalized databases are needed, together with addressing the challenges when utilizing the PEF methodology in real-world applications, to address primary sector large variability. For that, the PEF methodology was applied in 2 beef farms which grow calves from 120 kg to 410 kg fed with 2 different feed compounds each (growing and finishing). Data gathering was performed at the distribution gate including the following stages: raw milk production at farm, transport to dairy centrals, milk processing and packaging, and transport to market and supermarket centrals. The contribution analysis showed that the farm was the life cycle stage with the major contribution to the environmental impact (65% or more in all 16 PEF indicators). Results at farm gate showed the overall importance of the feed production impact (between 30% and 90% of the impact at farm gate in all indicators). Looking specifically at climate change (CC), emissions produced at the farm from manure management and enteric fermentation (IPCC & EMEP/EEA, 2019) were a major contributor to the impact: 19 and 36% contribution to CC respectively. Results of this study showed an average final carbon footprint of 6.62 kg CO2 eq per kg body weight at farm gate, what corresponds to 12.00 kg CO2 eq per kg carcass at farm gate (55% carcass dressing). This value increases slightly to 12.7 kg CO2 eq per kg carcass meat at distribution gate. These results are considerably below the benchmark value found in literature of 32.5 kg CO2 eq per kg carcass meat sold to retailers (TS Red meat FCR, 2019). This benchmark is calculated considering an average mix of production systems and technologies using both dairy and beef enterprises (TS Red meat FCR, 2019). Currently, different feed alternatives are being studied with the aim to improve beef production sustainability, without compromising animal performance and wellbeing. These might include assessing alternative ingredients that are nutritionally equivalent to the major impact contributors, additives that reduce emissions, research for optimizing crop production rates, and assessing different geographical origin of ingredients where improved agronomic practices are used or where crop production is located in ecosystems with lower susceptibility to environmental impact.

334 Use of Feed Additives in Unweaned Calves with Compromised Gut Integrity After Transportation

Abstract The gastrointestinal tract of unweaned calves is compromised after the stress and feed restriction due to marketing and transportation. The use of feed additives to enhance intake and gut immunity at farm arrival could be a strategy to minimize those negative effects. A total of 70 dairy beef calves (50.9 ± 1.66 kg) coming from auction market and with a compromised gut integrity at arrival were used to evaluate the effect of various feed additives [FA; comprising palatability enhancers (PE), standardized olive pomace extract (OE), and tributyrin (TB)] on performance until 2 weeks after weaning. Calves were distributed in 5 treatments: calves fed milk replacer (MR) and concentrate without FA (CTR; n = 14); calves fed MR and concentrate with PE (PE; n = 14); calves fed MR with OE + PE and concentrate with PE (OEPE; n = 14), calves fed MR with TB + PE and concentrate with PE (TBPE; n = 14); and calves fed MR with OE + TB + PE and concentrate with PE (complete - COM; n = 14). At arrival animals received 2.5 L of MR twice daily at 12.5% and ad libitum concentrate feed. On day 35 of the study, animals were submitted to a social stress challenge, calves within one treatment were mixed for 24 h, and on day 36, calves returned to their home pens and the afternoon milk was removed. On day 42, all calves were weaned, and they were followed until day 56. Data were analyzed with a mixed-effects model. After transportation calves had an average of 1.6 ± 0.09 mg/L of serum Cr-EDTA the first week after arrival indicating that those calves had increased gastrointestinal permeability and a compromised gut barrier for a full week; consequently, concentrate intake during that week was decreased for all treatments (P = 0.56) with an average of 27 g·calf-1·d-1. An interaction between treatment and time (P < 0.01) was observed on concentrate intake the last two weeks of the study when calves were already weaned; on week 7, from day 42 to d 49, COM and TBPE calves had greater concentrate intake than CTR calves, and PE and OEPE did not differ among others; and on week 8, between day 42 and day 49, COM calves had the greater concentrate intake than CTR, while other treatments were in between. Although only numerical differences were observed in final BW, COM calves were heavier than the rest of the treatments at the end of the study. In calves with severe problems of gastrointestinal permeability at arrival, the mixture of palatability enhancers, standardized olive pomace extract, and tributyrin increases concentrate intake and potentially improve the recovery of the animals.

PSIII-22 Substituting Palm Oil By Polyunsaturated Fatty Acid Rich Oils Reduces Methane Emissions at a Different Degree Depending on Concentrate Formula of Dairy Beef Calves: in Vitro Screening

Abstract In dairy beef calves fed high-concentrate diets even methane emissions may be lesser than calves fed high-roughage diets there is still room to improvement. Substituting palm oil, an ingredient that is questioned by the impact on deforestation of some regions, by polyunsaturated fatty acids (PUFA) may be a good strategy that needs to be tested. Therefore, the aim of this study was to evaluate the rumen in vitro methane gas production by substituting palm oil by different oils rich in polyunsaturated fatty acids in two different concentrates in T1 the main protein source was SBM (8%) and in T2 the main protein source was corn DDG (15%); the remaining concentrate ingredients were 50% corn, 15 to 13% barley, 15 to 16% wheat middlings, beet pulp (5.5% in T1), 1.8% calcium carbonate, 0.5% salt, 0.2% premix. Palm oil was substituted (4 or 3.5 % in T1 or T2, respectively) by canola oil (CO), sunflower oil (SU) or soybean meal oil (SO), so 8 treatments were tested (T1, T1-CO, T1-SU, T1-SO, T2, T2-CO, T2-SU, T2-SO), which are rich in polyunsaturated fatty acids in two. Samples were 1-mm grinded at 1-mm and used in an in vitro digestibility assay as described by [Goeser and Combs (2009)]. The rumen liquid, obtained from rumens at slaughterhouse of beef animals fed high-concentrate diets with a close formula to T1 and T2, was strained through a cheesecloth, collected into pre-warmed thermal flasks, and kept at 39ºC until being used. Two incubation sets were done in parallel and in triplicate: one lasted 48 hours to calculate the DM digestibility; the second lasted 12 days to monitor the methane gas production. A tendency (P = 0.10) in the interaction among basal diet and oil source was observed in total methane production corrected by blank methane production; numerically the same trend (P = 0.14) was observed in net volume of CH4 per degraded DM. After 12 days, the least methane production values were observed in T1-SO and T2-CO (30 and 29 mL ± 4.6, respectively), while the largest methane values were observed in T1-SU (45 ± 4.6 mL) being the remaining treatments intermediate values (42, 39, 31, 38, 41 ± 4.6 mL for T1, T1-CO, T2, T2-SU, T2-SO, respectively). In conclusion, depending on the concentrate formula (protein source used) the effect of fat source used to substitute palm oil and reduce methane emission may differ.

PSII-29 Effect of Dietary Alpha-Amylase Enzyme Supplementation on Growth Performance, Eating Pattern and Carcass Quality in Crossbred Dairy Beef Bulls Fed High-Concentrate Diets.`

Abstract The aim of this study was to evaluate the effect of dietary alpha-amylase supplementation on growth performance and carcass quality in crossbred dairy beef bulls fed high-concentrate diets. Ninety-nine bulls (187 ± 2.6 kg of BW, and 146 ± 1.0 days of age) were grouped in 6 pens of 15 to 17 animals/pen and fed concentrate, straw, and water ad libitum. Pens were assigned to one of 2 treatments: 1) CTR (n = 51), no treatment; 2) RUM (n = 48), RumiStar600 CT concentrate inclusion (630 mg/kg DM, based on 600 kilo novo units (KNU) of alpha-amylase activity). After 168 days, using twelve 14-days periods to record daily concentrate intake per animal, daily water consumption per pen, and fortnightly BW per animal animals were transported to slaughterhouse within one month, the whole study lasted an average of 210 days. Also, on days 0, 42, 84 and 168 concentrate samples were collected for enzyme activity and nutrient content analyses. Carcass quality was recorded at the slaughterhouse. Data were analyzed using a mixed model. The BW was greater (P < 0.01; interaction treatment by time) in RUM than in CTR treatment from period 1 to period 12. Concentrate intake tended (P = 0.10) to be greater in RUM than in CTR treatment in periods 1, 9 and 10. Bulls from RUM treatment had a greater (P < 0.01) ADG and a better feed conversion ratio than CTR bulls in periods 8, 10 and 12. Water consumption was similar between treatments, and no health problems related to treatments were recorded. Treatment did not affect carcass conformation. Preslaughter BW (539 vs. 523 ± 6.4 kg, RUM vs. CTR, respectively; P = 0.01) and hot carcass weight (306 vs. 295 ± 4.1 kg, RUM vs. CTR, respectively; P < 0.01) were greater in RUM than in CTR bulls. Also, fatness grade tended (P = 0.08) to be greater in RUM than in CTR treatment (score 1: 8 vs. 25 %; score 2: 77 vs. 63 %; score 3: 15 vs. 12 %; RUM vs. CTR, respectively). In conclusion, dietary alpha-amylase supplementation (600 KNU of alpha-amylase activity/kg DM of concentrate) for at least 168 days improved growth performance and carcass quality in crossbred dairy beef bulls fed high-concentrate diets.

Condition of surplus dairy calves during marketing: A cross-sectional study

In North America, surplus dairy calves are sold soon after birth and often marketed through a third party (e.g., live auction, livestock dealer) before entering veal or dairy beef production. Previous work has demonstrated that a percentage of calves have failed transfer of passive immunity (FTPI) and clinical signs of disease on arrival at calf-raising facilities, but little is known regarding calf condition during marketing. The objectives of this cross-sectional study were to (1) estimate the prevalence of FTPI and poor health outcomes in surplus calves on arrival at livestock dealers, and (2) investigate the association between calf-level variables (body weight, sex, source) and health outcomes. Two livestock dealers in Ohio were visited 2 to 3 times per week, with approximately 28 calves enrolled in the study per visit for a total of 1,119 calves. One blood sample per calf was obtained to evaluate FTPI by measuring serum total protein concentrations (using a cutoff <5.1 g/dL). Calves were clinically evaluated for signs of arthritis, broken ribs or tail, dehydration, depression, diarrhea, fever, navel inflammation, and respiratory disease by 2 observers; health outcomes were dichotomized using clinically relevant cut points. Descriptive statistics were used to estimate the prevalence of calves with poor health outcomes. Multivariable logistic regression models were built to investigate the effect of body weight, sex, and source on health outcomes. Nineteen percent (206/1,091) of calves had FTPI.